Improvement in edge-planes



I. A. D'IJ'NHAM.

EDGE PLANES.

Patented Nov. 28,1876.

FATENT OFFICE.

ISAAC A. DUNHAM, or "BRocKToN, MASSACHUSETTS.

' IMPROVEMENT IN EDGE-PLANES.

Specification forming part of Letters Patent No. 184,767, dated November 28, 1876 application filed June 23, 1876.

and useful Improvements in Shoemakers Edge-Planes and I dohereby declare that the following is a full, clear, and exact description thereof, which will enable'others skilled in the art to which "it pertains to inake'an d use the same, reference being had to the accompa nying drawings, and to the letters of reference marked thereon, whichform a part of thisspecification.

In such drawings, Figures 1 and 2 denote opposite side elevations, Fig. 3a longitudinal section, and Fig. 4 an end elevation, of a shoemakers edge-plane, constructed in accord ance with my invention.

My invention relates to that class 'of devices termed edge-molding planes, as employed by shoemakers in molding the edges of boots and shoes, in which the molding-edge or part of the implement is formed in two portions, one of which is on the cutter andthe "other on the guard; and my invention consists in an improved edge-plane, consisting of a stock, a guard, a handle, and a cutter, the'latter being applied at its rear end to the stock by a fixed center or fulcrum pin, and provided with a setscrew, all being essentially as set forth.

In the edge-plane hereinafter explained I have sought to remedy sundry evils incident to this class of implements as heretofore constructed. Tools of this character, as ordinarily made, have had their handles arranged at, or nearly at, a right angle to the plane of the cutting-edge, so that when the tool is grasped in the hand of a workman, it has been found very difficult, if not impossible, to preserve the knife in the curved shank of a boot or shoe, so as to cause it to take out a uniform and even shavmg. rily made is the great difficulty experienced by a workman in adjusting it so as to maintain the edge of the cutter and its moldingsurface in due relation to the guard and its molding-surface, so that both molding-surfaces shall not only have the desired corre spondence of curvature to allow such parts to have a firm bearing upon the sole to be reduced, but the cutting-edge of the cutter be so Another objection to the tool as ordinawhen the handle is grasped bythe operator, and he is cutting the curve'd portious of the sole, the'arc of motionfshall correspond to the easy natural movement of 't he"wrist,"s'i1ch enabling the curvatures of the edge to be trim med and molded with as much c'ertainty'and ease as the plane portions of the'sol'e. 7

Another feature of my invention is the' simple method by which the knife is adjusted, the same being as hereinafter described. 7

In the drawing, A denotes the stock of the implement, the same being made of metal, and provided with a handle," B, which I prefer to make hollow for the sake of lightness. The

handle B isof a peculiar shape, as'shown in the drawing, and instead offbeing arranged-at a right angle to the cutting edge of theknife, ;l arrange it an acute angle thereto,"so'that, when grasped inthe hand of "a workman, greater freedom of motion may .be given to the knife,-'so as to" enable him to cut with equal facility through theshan'k and "curved'portion of the soleedge, as upon the plane parts thereof. With edge-planes as ordinarily constructed this cannot be done.

The stock A is cut away on both of its lateral sides, on the one side to receive one or more fingers of the operators hand, and on the other to receive the shank of the curved knife 0, which is pivoted at the rear end by a screw or pin, b, to the stock, as shown iu'Fig. 2. D is a set-screw, which extends through a curved slot, a, formed in the stock, and into the shank of the knife. Besides reoessing the stock A on its opposite sides, as and for the purposes herein mentioned, I arrange the bandle B obliquely to the stock-that is,'at an obtuse angle with the front edge of the stock, or that edge to which the guard is fastened, all being substantially as shown. In most, if not all, other edge-planes the handle has been essentially in a straight line with the stock,'or that edge of it to which the guard was applied.

My arrangement of the handle and stockthat is, obliquely to each other, as represent, ed-enables the implement to be worked to much better advantage, particularly in the shank or hollow of a sole, as any shoemaker will readily discover on trial of it.

E is the adjustable guard, the same being connected to the front face of the stock by a spline and feather connection, as shown in Fig. 3. I) is a set-screw, which extends through an elongated slot, 0, formed longitudinally in the said guard, and into the stock,the object of such arrangement being to enable the guard to be either raised or lowered in order to allow the cutter to remove the desired thickness of shaving. Both the cutter and the guard are formed with a correspondingly-curved molding-surface, the curved face oi the knife or cutter being the are of i a circle whose center is the fixed pivot b of the cutter, the curved slot 0, in the stock being concentric with the curved molding-surface of the cutter. construction and arrangement of parts a large and open throat or chip passage, 0, is formed on the implement, so that there is no liability of the same ever becoming choked, as often results with articles of this class as ordinarily made.

If we suppose the parts of the tool to have been put together, and the molding-surface of the cutter and knife to have been filed and ground to a corresponding curvature in order to adapt the tool for use, we have simply to lower the guard (by means of the screw 1)) to obtain any desired thickness of shaving, the set-screw D enabling the cutting-edge to be brought up and maintained, as it may become worn, in due relation to the guard.

From'the above it will be seen that by affixing the cutter to the stock on a fixed center, and forming the molding-surfaces of the cutter and guard, as arcs of the same circle of which the knife-pivot is the center, a novice can as readily and accurately adjust the tool for use as the most skilled mechanic, as all By this.

that is necessary after the guard has been once adjusted (to give the required thickness of shaving) is to move the cutter on its center of motion and affix the set-screw D, so as to maintain it in proper relation with the guard, as such knife may become worn.

In using my improved tool the operator grasps the handle between his thumb and fin gers, bringing the ends of the two shorter fingers to rest upon the cut-away part of the stock,as shown at c in Figs-1. and 4', and brings the molding-edge of the tool upon the edge of the sole, and manipulates the same in the usual manner, the peculiar method of arranging the handle with respect to the cutter enabling the tool to be used with as great ease and facility on the curve as the plane portions of the edge.

What I claim as my invention is 1.. The improved edge-plane, consisting of the stock A, guard E, handle B, and cutter O, the latter being affixed at its rear end to the stock by the fixed center or fulcrum pin (1, and provided with the set-screw D, the whole being constructed and arranged for conjoint operation, as shown and described.

. 2. The stock A recessed on its opposite sides, in manner and for the purpose substantially as shown and described.

3. The stock, recessed on its opposite sides, as described, in combination with the handle, arranged obliquely to the stock, or at an obtuse angle to its front edge, all being substantially as represented.

In testimony that I claim the foregoing as my own invention I aflix my signature in presence of two witnesses.

ISAAC A. DUNHAM. 

